China continues to suppress religious rights of Tibetans as they maintain control over them, an official US report has said.

According to the annual US report on International Religious Freedom for the year 2013, the Chinese government routinely denigrated the Dalai Lama, whom most Tibetan Buddhists venerate as a spiritual leader, and blamed the "Dalai Clique" among other outside forces and foreign media reports for instigating self-immolations.

"They (Chinese authorities) arrest Tibetan Buddhists simply for possessing the Dalai Lama's photograph," US Secretary of State John Kerry told reporters after releasing the report.

The Assistant Secretary of State for Democracy, Human Rights and Labor Tom Malinowski said that in Tibet, authorities continue to assert control over Tibetan Buddhist religious practices.

The Chinese government also severely restricts the religious practices of Uyghur Muslims, including banning fasting during the month of Ramadan for civil servants, teachers and others, he said.

"Authorities often justified official interference with Tibetan Buddhist monasteries by associating them with separatism and pro-independence activism," the report said.

There were reports of Tibetans encountering societal discrimination in employment, while engaging in business or when travelling, but because Tibetan Buddhists ethnic identity is closely linked to their religion, it can be difficult to categorise incidents of intolerance as purely ethnic or religious, the report added.

Noting that the government's respect for and protection of religious freedom in Tibetan areas were poor, the report said there were numerous and severe government actions affecting religious freedom including incarceration of people due to religious practices and three reports of deaths at the hands of the police or while in police custody.